Vital review on a country (6)
I believe the answer is:
latvia
'country' is the definition.
(Latvia is a European country)
'vital review on a' is the wordplay.
'review' indicates an anagram.
'on' indicates putting letters inside (as in clothing 'on' a person).
'vital' is an anagram of 'ltvia'.
'ltvia' placed around 'a' is 'LATVIA'.
(Other definitions for latvia that I've seen before include "European republic, capital Riga" , "Baltic country" , "Riga's country" , "Baltic state, capital Riga." , "Baltic republic" .)